Types

Radiation therapy, like cancer itself, has a bit of social stigma attached to it. It is referred to by the lay public by various gory terms such as sikaai, bijli ki sikai, bijli ka jhatka, jalana and so on. Some patients consider it akin to physiotherapy and heat therapy. These misnomers and misconceptions have further augmented the fears and apprehensions of cancer patients. Even general practitioners have some erroneous beliefs about this treatment modality. Given that nearly 60% of all cancer patients would require this modality of treatment, it is time we give up many of these misconceptions.

Radiotherapy means treatment of cancer by special x rays (or in some cases gamma rays). These rays are special because unlike ordinary x rays, these rays have much higher energy and much higher precision for accurate treatment delivery. Starting with very simple and crude techniques nearly a century ago, radiation oncology or radiotherapy has come of age in the past 3 decades. Traditionally radiation area used to be empirically marked on the patients body by the treating doctor. With advent of diagnostic x ray based imaging, treatment area (or fields) started being marked based on bony landmarks. In early 1970’s the CT scanner arrived and very soon radiation oncologists started using CT based methods for radiotherapy planning (also known as simulation). With this arrived 3 dimensional conformal radiotherapy (3D CRT, intensity modulated radiotherapy (IMRT) and image guided radiotherapy (IGRT). Using these, the oncologists could draw the tumour area and the normal structures slice by slice in the planning system computers, enabling much higher degree of efficiency in treatment.

Oncologists soon realized that some sites are more mobile during respiration and their planning requires information regarding their motion (such as lung tumour and some liver tumors). This lead to development of techniques called 4 D (4 dimensional, the fourth dimension being time). Such advanced modalities enable further accuracy in radiotherapy treatment, enabling the radiation oncologist to spare critical normal structures adjacent to tumor region.

As an example, breast conserving therapy (BCT) is now a standard treatment in the management of early breast cancer. Patients suffering from breast cancer can now retain their breasts using this technique. This has been enabled by organ sparing surgery followed by local radiotherapy to the breast area. The major benefit of Breast conservation is the preservation of the affected breast with significant consequent advantages in terms of psychological function and quality of life.

Modern radiotherapy has proven to significantly reduce the adverse effects to adjacent organs for nearly all sites, including breast cancers, lung tumor, brain tumors, abdominal and pelvic tumors.

While multitude of modern equipment and technology are available, it needs to be executed by a radiation oncologist well versed and experienced in these techniques. This is an important point, often ignored by patients. Many patients land up asking for a particular technology, not appreciating that every technology use needs an expert hand as well.

Patients have other misconceptions about radiation which need to be cleared. The following facts are therefore being presented. External radiation therapy by x rays (or gamma rays) does not make one radioactive. The patients undergoing treatment can have contact with friends, children and others. It is a completely painless procedure. Unless the patients are having other ailments, they usually tolerate the treatment quite well and are able to lead an active life during treatment course and beyond. Also radiotherapy is a local treatment (just like surgery is a local treatment) and does not have much impact on sites away from the target area. However, as in the case of other diseases, no two patients are the same and their tolerance even to the same treatment can be different.

To summarize, radiation therapy is an efficient tool in management of cancer. For a modern day cancer center, radiation therapy unit is an absolute must. High level evidence coupled with modern radiotherapy technology has led to emergence of a new horizon in radiation cancer care.